: You can get it directly from the Archipack official store.
: It is also available on popular creator sites like the Blender Market. How to Install a Downloaded .zip File Download Archipack Addon for Blender
If you purchased the Pro version or downloaded a custom build, follow these steps to install it: : Do not extract the folder. Go to Edit > Preferences > Add-ons . Click the Install... button in the top right corner. Select your .zip file and click "Install Add-on." Activate it by checking the box in the Add-ons list. Why use Archipack? : You can get it directly from the Archipack official store
Blender comes with a standard version of Archipack pre-installed. You just need to activate it: and navigate to Edit > Preferences . Select the Add-ons tab on the left. Search for "Archipack" in the search bar. Check the box next to Add Mesh: Archipack to enable it. Go to Edit > Preferences > Add-ons
For more help, you can check the official documentation or community forums like Blender Artists.